Detection of Prebiotic Molecules in Titan Analog Materials in support of the Dragonfly Mass Spectrometer Investigation
Abstract
Titan's thick N2 and CH4 atmosphere hosts a rich organic chemical synthesis, initiated by solar radiation and energetic particles from Saturn's magnetosphere. A variety of volatile atmospheric organics have been detected. Reactions among these result in organic aerosols that form a visible atmospheric haze. While the only direct analysis of Titan's aerosol composition gave partial results (Israel et al., 2005), laboratory experiments simulating Titan's atmospheric chemistry have yielded a wide variety of organic molecules based on C, N and H atoms (e.g., Hörst et al., 2018), including prebiotically important nitrogen-bearing molecules such as amines (Cable et al., 2014), nucleobases and possibly amino acids (Hörst et al., 2012). Once deposited at the surface, the solid organic materials may be exposed to geophysical processes that promote chemical evolution beyond the atmospherically generated population. Notably, in certain regions organics may have been exposed to transient liquid water, such as in putative cryovolcanic regions or impact craters (Neish et al., 2018).
One major goal of the Dragonfly mission, recently selected under NASA's New Frontiers Program, is to measure the compositions of Titan surface materials found in sites that are representative of different environments such as dunes and icy surfaces. Chemical analyses of these materials by the Dragonfly Mass Spectrometer (DraMS) will be performed with Laser Desorption/ionization Mass Spectrometry (LDMS) and Gas Chromatography Mass Spectrometry (GCMS). These two complementary analytical techniques combine to allow detection of compounds with a wide range of mass and chemical functionalities. This dual approach is soon to be demonstrated with the Mars Organic Molecule Analyzer (MOMA) experiment on the Rosalind Franklin rover to be launched to Mars in 2020 (Goesmann et al., 2017). We present LDMS and GCMS techniques that will be used to perform in situ analysis of materials collected at Titan's surface, demonstrating the detection of chemical compounds of interest to prebiotic chemistry and analysis of analog materials that represent Titan's complex organics.- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.P23D3538H
- Keywords:
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- 5210 Planetary atmospheres;
- clouds;
- and hazes;
- PLANETARY SCIENCES: ASTROBIOLOGY;
- 6207 Comparative planetology;
- PLANETARY SCIENCES: SOLAR SYSTEM OBJECTS;
- 6281 Titan;
- PLANETARY SCIENCES: SOLAR SYSTEM OBJECTS;
- 5405 Atmospheres;
- PLANETARY SCIENCES: SOLID SURFACE PLANETS